In addition to the 400+ heating and cooling cycles, I'm really interested to see if there has been any visible evidence of electrostatically-induced movement of dust. There was speculation that the day/night cycle caused electrostatic transport of dust particles - I don't know how big those dust particles are, but 40 years elapsed time may be enough to result in reduced reflectivity on some of the hardware.

Actually we know how close the Apollo 14 crew got to Cone Crater's rim, because we can compare the boulders seen in their surface images at Station C1 with the Lunar Orbiter images of the same boulders. They didn't know at the time, but we know it now. They were about 40 m from the rim but couldn't see over it into the depression. It will still be great to see these places at unprecedented resolution, but it won't change our ideas about the location of C1.

I don't know how big those dust particles are, but 40 years elapsed time may be enough to result in reduced reflectivity on some of the hardware.

A research paper of possible, related interest that appeared in Geophysical Research Letters last April might be something to have a look at -- titled "Direct active measurements of movements of lunar dust: Rocket exhausts and natural effects contaminating and cleansing Apollo hardware on the Moon in 1969"

The paper does get quite technical in parts, however, to have a read go HERE, or for a more 'readable' version see this ScienceDaily article.

A research paper of possible, related interest that appeared in Geophysical Research Letters last April might be something to have a look at -- titled "Direct active measurements of movements of lunar dust: Rocket exhausts and natural effects contaminating and cleansing Apollo hardware on the Moon in 1969"

The paper does get quite technical in parts, however, to have a read go HERE, or for a more 'readable' version see this ScienceDaily article.

John

ADDENDUM: Sorry Space Angel if you're having problems accessing the first link as I don't want to point you to a subscripe/purchase option -- which it does. I did a check on the availability of it using the link at the end of the ScienceDaily article and I swear I got acces to the complete article after clicking on 'Full Article' in Geophysical Research Letters. But for some reason it doesn't allow me in anymore on a second try. You might try it at your end as it may have only allowed me access it once (I tried it again just now but, darn it, I'm being put into the subscribe'purchase link.

Sorry if it doesn't work...but the ScienceDaily article does work okay.

Also potentially pertinent to the appearance of the Apollo lunar surface hardware is the work that is currently underway at the National Air and Space Museum to replace all the Kapton foil on LM-2, which has been sitting in sunlight at least part of every day for the past 33 years. There's a more detailed summary of the restoration work underway at collectspace.com, but what I thought was particularly interesting was this little snippet:

QUOTE

They bagged the Descent Stage with a giant sheet of polyethylene, then hung some sheets of 2 mil Aluminized Kapton which crumbled after 33 years in the sun! Some samples of that are being analyzed, and the rest is trash unfortunately. It just broke apart and was covered in dust and filth!

If the Kapton crumbled after 33 years in a climate-controlled environment, even with partial sun every day, one wonders as to the state of the Kapton that has been sitting in lunar conditions for 40 years, and if any of this deterioration might be visible from LROC.

Indeed. There's mounting evidence that Kapton isn't really very durable over time, esp. when exposed to extreme heat. I suspect that the material on the descent stages may have long since crumbled away.

--------------------

A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.

Just look at Hubble Insulation. It's crumbling off. It may be going thru more rapid thermal cycles than Apollo hardware - but there's evidence that long space exposure does end up ruining that sort of insulation material.

There are a lot of other interesting potential variables to consider, too. For example, the Apollo stuff's obviously exposed directly to the solar wind while Hubble isn't, but at the same time HST is exposed to monatomic oxygen in LEO. Does any of that make any difference? Dunno.

All we seem to know with high confidence is that kapton looks very stable for 5-10 years--long enough for most nominal missions to date--of exposure to the inner Solar System space environments we've spent the most time in, but prospects don't look promising for much longer durations.

--------------------

A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.

I was the contractor on the LM-2 job. I was really shocked at the quality of the sun-facing Kapton sheets. They only had the 2 mil aluminized Kapton on LM-2 and it broke apart in your hands - not brittle, just a kind of mushy break. It was very dull - looked a bit like the Vbar side of the Kapton coverings from the early Shuttle flights (the elbow camera on the arm for example) which got "eaten" away by atomic oxygen in low earth orbit. For LM-2 we replaced the old stuff with proper variations of Kapton (1/2, 2 and 5 mil thicknesses) so if the complete restoration is not done soon, we might get some idea about how different thicknesses of Kapton handle the heat and light in the relatively benign environment of the museum.

QUOTE (nprev @ Jun 27 2009, 10:36 PM)

Indeed. There's mounting evidence that Kapton isn't really very durable over time, esp. when exposed to extreme heat. I suspect that the material on the descent stages may have long since crumbled away.

Well, the multi-layer blankets (~20-30 sheets) were constrained around standoffs and were well built with taped seams and different hardware to hold them together. We might see the outer layer, which was screwed to the standoffs, crumble, but the inner layers will peel in sections - my guess is that there will be quite a bit left on the spacecraft once the exterior sheets have popped off from the stresses of their attachment.

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